Apparatus for recovering valuable constituents from ores.



APPLIOATION FILED JAY: 17, 1910.

Patented July 21,1914

IN VENT R WITNESSES;

- {ATTORNEY FREDERICK H. PRENTISS, OF SAN A'EENT FRANCISCO, CALIFORNIA, ASSIGNOR ONE-HALF TO LEDA. B.- PRENTISS, OF SAN FRANCISCO, CALIFORNIA, AND ONE-HALF T ROBERT C. LANE, 0F BERKELEY, GALIFORN IA. v

APPARATUS FOR RECOVERING VALUABLE CONSTI'IUENTS FROM ORES.

Specification of Letters Patent.

Patented July 21, 1914..

Application filed January 17, 1910. Serial No. 538,409.

f To all whom it mayv concern Be it known that I, FREDERICK H. FREN- rise, a citizen of the United States, residing at San Francisco, in the county of San stituents by the combined actions of cen-i trifugal force, and that of an opposing current'of a fluid, preferably water, and pref-2 erably an-intermittent 0r pulsating current.-

In the accompanying drawings, Figure 1 is a broken vertical section of one form of my improved apparatus, in which thetailings are discharged at the bottom; Fig. 2 is a similar view in which the failings are discharged at the top; Figs. 3, 4 and 5 are sections on the lines 3-3, 4-4, 5-5, respectively, inFig. 1. 1

. Referring to the drawings, and particularly .to that form of the apparatus shown in F ig. l, 1 indicates a shaft to;whichrotation is imparted by any suitable means, not shown. The lower portion of said shaft is hollow, as shown at 2, and passing upwardly into said hollow shaft is a stationary watersupply pipe 3. Screwed upon-said hollow shaft are sections 4, 5 and 6 of a rotor. The uppermost section 4 is formed with a. surface of revolution which is of ageneral bellshaped form but widened at the bottom. Uponthis surface the .pulp 7 is discharged from pulp-supply pipes 8. Said pulp flows over the surface of said section 4, and'between said surface and the inner surface of a shell 9, which, bymeans of a ring of screws 10, is secured to the rotor section 4, the shapes of said rotor section and shell being such as to provide a space therebetween of substantially uniform thickness. Through this space the pulp flows by gravity, its Speed being accelerated by centrifugal action, and presses against an inner curved surface 11 of said shell 9. Said shell 9 1s additionally secured to the upperrotor section 4. by pipes 12, which pass through the shell and connect at their innerends with an annular water passage 13 open to the interior of the pipe 3 by an opening 14 through the rotary shaft 1, which opening ll, during part of the rotation of said shaft, connects through an opening 15 with the interior of the water supply pipe 3.

The second rotor section 5 comprises a hub portion screwed upon the rotary shaft, conduits 16 leading radially therefrom, and a rim portion 17 formed integral with said conduits and perforated, as shown at 18 to form continuations of the conduits. The

jlowermost rotor section 6 is, in like manner formed of a hub portlon 19, radial conduits 20, and a rim portion 2-1. -Connecting the shell 9 with the rim portion 7 is a cylindris cal wall having a flanged portion 23securcd by screws 24 to the rim portion 17, but spaced therefrom a short distance by washers 95 to form a passageway 26: to permitthe valuable material to pass therebetwcen. In like manner the'riln portion 17 is secured to the rim portion 21 by awall 27 having a flange portion 28 spaced from the rim portion 9.1 to form a passageway-29,

and, in like manner, the rim portion 21. is secured to a ring 30 by a wall 31 having a flange 32 secured by screws 33 to said ring, and spaced therefrom to form a passageway 34; A-casing 35 secured at the top of the flanged portion 23, and at the bottom to studs '36 formed on the outer edge of'the ring 30 furnishes a closure for the aboye mentioned parts, the discharge from within said closure being into a hutch launder 37.

Between the shell 9 and the rim portion 17 extends-a conical screen 38, sloping inwardly downward. A screen 39'is similarly arranged between the rim portion 17 and the rim portion 2-1 and a third screen 40 lsslnnlarly arranged between the rim 21 and the ring 30. A clear water launder 41 is arranged immediately beneath the inner edge of the ring 30. These screens are preferably arranged so that each is of finer mesh than the one above it, corresponding to the variations in diameter of said screens and the consequent increase in centrifugal force thereagainst. Thus, if the diameters of the respective screens are to each other in the' proportions of 9., 3, and 4, the screen meshes will be 20, 30, 40, or 40, 60, 80, according to' the fineness of the pulp under treatment.

. The method of using the apparatus will material falls ofi" the inside of the ring 3O.

readily be understood from the foregoing description.

The shaft having been set rotation, and

the pulp discharged from the pipes 8, said pulp is,by centrifugal force,directed against the first of the above described screens, where it meets resistance from the pressure of the water between said screen and the wall 22 This pressure is suflicient to wash inward the gangue and light material, on which the centrifugal action has the least eiiect, but the heavy material is forced through the screen against the pressure of the water. This action is repeated at the successive screens until finally all of the valuable material has been passed through the screenswhile the gangue and worthless This worthless material will by centrifugal force divide into two streams, the heavier material passing outside the upper edge of the outerwall of the clear water launder, while the clear water falls into said launder, by which it is led to a storage tank, from which it can be pumped'back for re-use. It

, will have been observed that, by reason of the fact that the water chambers between the screens 38, 39,40, and the walls 22, 27

4 31, are each in communication with the water supply during part only of a complete revolution of the rotary shaft, the water pressure which opposes the centrifugal action is a pulsating or intermittent pressure,

the arrangement being such that each chamber in turn receives the increase in pressure.

,In concentrating a galena ore crushed to 80 mesh, all of v the galena, including the finest slinies, should be recovered as a hutch f product of practically pure galena through the 20 mesh screen, while the tailings should not show more than a trace of lead. a

60 mesh screen using pulp of 200 mesh, all. of the galena should be recovered as a hutch product of practically pure gale'na while i the tailings should not show more than a trace oflead, and all quartz coarser than 18 or 20 mesh shouldibedischarged as tailrings. Similar statementsmay be made of gold, wrr ee ury, and the -lik e. v g Th height of the passages 26, 29, 34, may

I be regulatedby the screws, so that only the least amount. of waterfmay be discharged- 7' with the hutch product'that-is actually re'-' uired for the-removal of the valuable particles of high specific gravity. With a; ga-

1ena quartzore 'crushedtoq mesh thegreatest rticlesfoi *gal'ena thatiwo d go intoh amhwoua beab j passage of anything 61115;:20 the in erstitial space-tame tlieipafticles formody off-ore rest-j permlttlngthe ing the bed ofthe jig, b mg agamstjthe screen,. ot I H w oarser. I The pulsatcurrent. flowing inwardlythrough the 7 screen, and through the forming ticles of quartz finer than mesh and discharge them as worthless tailings.

In the form of the appartus shown in Fig. 2, the pulp is discharged by pipes 42 on to the top of a spreader 43 secured to, and suspended from, a rotating shaft 44, the bottom 45 of a vessel 46 being secured to the spreader by means of screws 47 through bosses 48 formed on the spreader 43. To the upper edge of the vessel is secured by said rim depending into the first or inner section of a combination launder, said launder having four annular walls 53, 54: 55, 56, forming a hutch launder 52, atailingsdischarge launder 57 and a clear water launder 58. Between an annular horizontal flange 59 of said rim and the outer edge of the connection to said screen a sufiicient distance to insure a bed of ore of sufiicient thickness being pressed against said screen by centrifugal action. To the middle of the bottom of said vesselis secured a hollow shaft 61 which depends into a stufing box 62 secured upon an outlet mouth 63 of a tically before beingfixedly secured to the vessel by' means of said screws. a

.By centrifugal action,"the pulp is pressed ainst the rotating screen, and by this force alone all of the solid particles of the pulp are deposited in a layer'along the surface of said screen. not here shown, the pressure of the water in the pipe 64, and also in the space between the vessel and the screen, is a pulsating'or intermittent pressure. Owing, however, to

water passing-inwardly thronghthe screen,

the lighter particles or gan e are swe t back and are discharged bytl i p v are caught beneath the curved edge-- of the wall 55 and pass. mt'o' the tailings launder,

and falls: into the clear waterlaunder;v

the bed of the jig, would carry off allpar screws 49 to lugs 50 on said edge, a rim 51,

spreader is secured a conical screen 60, said flange extending inwardly past its point of the pulsating or intermittent current of pipe 64 which is connected to a pressure permitting of the rim being adjusted verno I By suitable contrivanoes-f e overflow of I the stream.of waterabove the horizontal 1 flange of the mm. The tailings discharged r a nea sake of n mes- Ihave, in

the descriptmn 0 myinventiomspoken of. 7 water asi'the' carrier-70f the pulverized ore, {so

I 123 whllefithelclear water passes; over said edge I do not limit myself to the use of this fluid,

since any suitable liquid may be employed, or even a gas, such as common air.

I claim A rotatable vessel having an invertedcone-shaped screen concentric with the axis of rotation and permanently secured to, and

within, the wall of the vessel to form with said screen a closed annular Space said screen being. of a mesh adapted to permit passage therethrough of the particles to'be separated, a layer of material resting upon the screen and forming a jig bed,omeans for forcing a stream of'water into said closed space between said wall and screen and through the material forming the -jig bed,

my hand in the presence of two subscribing I witnesses. v

FREDERICK H. PRENTISS.

Witnesses G. C. DE WOLFE, C. C. BAKER. 

